Fluid control apparatus



July 9, 1963 P. HOLLINGSWORTH FLUID CONTROL. APPARATUS 2 Sheets-Sheet 1 Filed Dec. 4, 1961 INVENTOR. PIERCE HOLLINGSWORTH ATTORNEY y 1963 P HOLLINGSWORTH 3,09

FLUID CONTROL APPARATUS 2 Sheets-Sheet 2 Filed Dec. 4, 1961 FIG-8 INVENTOR. PIERCE HOLLINGSWORTH ATTORNEY United States Patent 3,096,828 FLUID CONTROL APPARATUS Pierce Hollingsworth, Wayland, Mass, assignor to Standard-Thomson Corporation, Waltham, Mass, at corporation of Delaware Filed Dec. 4, 1961, Ser. No. 156,776 10 Claims. (Cl. 170160.14)

This invention relates to fluid control apparatus. The invention relates more particularly to structure for movement of air or other gas. The invention relates still more particularly to thermally controlled fan apparatus.

In many types of mechanisms it is desirable to have fan apparatus which is thermally controlled so that the movement of air or other gas is dependent upon the temperature thereof. For example, in association with a radiator of an internal combustion engine, it is desirable to have fan apparatus which causes movement of air through the radiator in accordance with the temperature of the air.

A problem in regard to any fan apparatus relates to the fact that noise is caused by movement of air or other gas by the fan apparatus. Ordinarily, the noise level is dependent upon the volume of air moved by the fan apparatus.

It is an object of this invention to provide adjustable pitch fan apparatus which is thermally controlled.

Another object of this invention is to provide such apparatus which has a minimum number of moving parts and which is comparatively simple and inexpensive to construct.

Another object of this invention is to provide such fan apparatus in which the mechanism for adjustment of the pitch of the blades has small physical size and which requires a minimum amount of space.

Another object of this invention is to provide such fan apparatus in which the pitch control mechanism comprises elements which are comparatively simple to construct and to assemble.

Another object of this invention is to provide such fan apparatus in which the pitch angle of the blades is auto matically dependent upon the rate of rotation thereof, as well as being dependent upon the temperature of the air or other gas moved by the blades.

Other objects and advantages reside in the construction of parts, the combination thereof, the method of manufacture, and the mode of operation, as will become more apparent from the following description.

In the drawings:

FIGURE 1 is a perspective view showing apparatus of this invention.

FIGURE 2 is an enlarged fragmentary view, with parts broken away and shown in section, of a portion of the apparatus of this invention.

FIGURE 3 is a sectional view taken substantially on line 33 of FIGURE 2.

FIGURE 4 is a sectional view taken substantially on line 44 of FIGURE 2.

FIGURE 5 is a fragmentary View similar to FIGURE 2 but showing elements of the apparatus in another position of operation.

FIGURE 6 is a sectional view taken substantially on line 66 of FIGURE 5.

FIGURE 7 is a sectional view taken substantially on line 7-7 of FIGURE 5.

FIGURE 8 is a fragmentary view similar to FIGURES 2 and 5 but showing elements of the apparatus in still another position of operation.

FIGURE 9 is a sectional view, taken substantially on line 99 of FIGURE 8.

Referring to the drawings in detail, apparatus of this invention comprises hub structure 10 which may be attached to any suitable shaft 12 for rotation thereof. Here- ICe in bolt members 13 are shown for use in such attachment.

The hub structure 10 is shown as including a pair of plates 14 and 16 which have opposed bent portions 18 and 20, respectively, which form a plurality of housings at spaced apart positions. Bolt members 22 extend through the plates 14 and 16 for attachment thereof one to the other.

Within each housing which is formed by the bent portions 18 and 20 is carried a stem 24. Any suitable bearing structure 26 may be used to rotatably support each stem 24, as best shown in FIGURE 2. A larger diameter portion 28 of the stem 24 is shown within larger bent portions 29 of the plates 14 and 16 to retain the stem 24 against axial movement. Thrust bearing portions 30 engage the larger diameter portion 28 of the stem 24.

Each stem 24 has an extension portion 32 to which is rigidly attached a blade 38.

Each stem 24 has a cavity therein within which is disposed a quantity of thermally responsive expansiblecontractible material 49' which may be of any suitable known type and which has the desired expansion characteristics over a given temperature range. Within the cavity of each stem 24 is a plunger or piston member 42. Each plunger 42 is shown as being in direct engagement with the thermally expansible-contractible material 40. However, if desired, suitable sealing means may be used be tween the plunger 42 and the material 40.

Each plunger or piston 42 has a rod 44 which extends through a key member 46. The key member 46 has a shank 48 and an engagement portion 50. The engagement portion 50 slidably fits within a complementary cavity section of the stem 24. The key member 46 also has an extension portion 52. A bearing 54 is shown in contact with the extension portion 52 of the key member 46. The key member 46 thus is slidably axially movable within the stem 24, but the key member 46 and the stem 24 rotate one with the other.

The extension portion 52 of the key member 46 is shown as being hollow and the rod 44 of the plunger 42 extends into the extension portion 52. A nut 56 is attached to the rod 44 within the extension portion 52. The extension portion 52 of the key member 46 is provided with cam means in the form of a plurality of cam slots 57. A plurality of pins 58 are fixedly carried by the hub structure 10. Each pin 58 slidably fits into one of the cam slots 57 of the extension portion 52. Thus, with axial movement of the key member 46, there is also rotative movement thereof.

Resilient means in the form of a helical compression spring 66 encompasses the rod 44 intermediate the shank 48 of the key member 46 and the piston or plunger 42. The compression spring 60 urges the piston 42 in a direction from the key member 46. However, the nut 56, at tached to the rod 44 and engaging the key member 46, limits the movement of the piston 42 with respect to the key member 46, as best shown in FIGURE 2. The position of the nut 56 upon the rod 44 thus determines the compression of the spring 60'.

Operation As stated above, the shaft 12 may be used for rotation of the hub structure 10. The shaft 12 may be rotated at any desired rate. Ordinarily, when the fan structure is used in connection with a cooling system of an internal combustion engine, the rate of rotation of the fan structure varies with the speed of the engine. Rotation of the hub. structure 10 causes rotation of the blades 38 about the axis of the shaft 12. When the temperature of the air which comes in contact with the hub structure 10 is below a given value, the thermally responsive material 40 within the stems 24 is of such a volume that no appreciable pressure is applied upon the plungers 42. Under 3 such conditions, there is no force urging pivotal movement of the blades 38.

Thus, movement of the blades 38 with rotation of the shaft 12 and the hub structure 10 causes the blades 38 to be feathered, i.e., to be disposed in substantially the same plane as the plates 14 and 16. The blades 38 assume this feathered position due to the fact that the blades 38, unless urged to angular positions, obtain positions of least resistance to the movement thereof through the air. Thus, when the temperature of the air contacting the hub structure 10 is below a given value the blades 38 are positioned as shown in FIGURES 2 and 4.

When the temperature of the air which is in contact with the hub structure 10 is above a given predetermined value, the thermally responsive material 40- expands to assume a greater volume. This expansion of the material 40 forces the plunger or piston 42 to move in a direction from its respective blade 38, as shown in FIGURE 5. The compression spring 60 is of such capacity that the spring 60 normally transmits the forces from the piston 42 to the key member 46 without appreciable additional compression of the spring 60. Thus, the key member 46 is forced to move in a direction away from the blade 38, as shown in FIGURE 5. As each key member 46 is so moved in a direction from its respective blade 38, the key member 46 is caused to rotatively move. This is due to the fact that the cam slots 57 in the portion 52 of the key member 46 cause rotative movement thereof as the key member 46 moves axially. Each key member 46 causes its respective stem 24 to rotate therewith. Such rotative movement of each stem 24 causes ro-tative movement of each stem 24 causes rotative movement of its respective blade 38 and the blades 38 become positioned as shown in FIGURES 1 and and as shown in solid lines in FIGURE 7. Thus, a greater volume of air is moved by the blades 38.

If, after the elements are positioned as shown in FIG- URE 5 further heating occurs so that the temperature of the material 48 rises further, the material 40, of course, expands further. Therefore, the plunger 42 is moved farther in a direction from the blade 38. When the pins 58 are positioned at the end of the cam slots 57, the key member 46 cannot move farther in a direction from the blade '38. However, if additional heating occurs, the spring member 60 compresses to permit further movement of the plunger 42 in a direction from the blade 38. Thus, the spring 60 serves as -a safety element to prevent creation of excessive forces upon the key member 46 or upon the pins 58 if excessive pressures arise in the ma terial 40.

If the temperature of air which engages the hub structure is again reduced, the volume of the thermally responsive material 40 is reduced so that the pressure of the material 40 upon the plungers 42 is reduced. Thus, each plunger 42 is permitted to move in a direction toward its respective blade 38 and the blades 38 rotatively move toward feathered positions.

As stated above, a moving fan blade causes considerable air noise. Usually, the amount of noise of the moving air is dependent upon the volume of the air moved. Thus, if a fan apparatus should be rotating at a high rate of speed with a large pitch angle of the blades thereof, the volume of air moved would be great and thus the amount of noise created would be great. If such fan apparatus should be used in connection with a cooling system of an internal combustion automobile engine, the noise created by the high volume of air moving through the cooling system might be objectionable.

Because of the conditions of road speed of the automobile and because of conditions of flow of cooling fluid within the cooling system of the automobile engine, the volume of airflow may not need to be so great and thus the pitch angle of the blades of the fan apparatus might not need to be so great. In other words, the large angle of pitch of the blades 38 as established by the thermally reduced at rotational speeds above a given value.

upon the key members 46 become greater.

responsive material 4%) might not be necessary in consideration of the actual conditions within the cooling system of the engine associated therewith.

The apparatus of this invention includes means for automatically adjusting the angle of pitch of the fan blades 38 in consideration of the rate of rotation of the hub structure It). For purposes of illustration it is assumed that the temperature of the air engaging the hub structure 18 has caused expansion of the thermally responsive material 48 so that the blades 38 are at a considerable angle, as shown in FIGURES 1, 5, and 7. When the hub structure 10 is rotated above a given rate, centrifugal forces upon each key member 46 cause the key member 46 to act against the forces of the spring and the key member 46 moves toward the blade 38, as shown in FIG- URE 8.

Movement of the key member 46 toward the blade 38, Without changes occurring in the volume of the material 48, is permitted as the spring 60 is further compressed. As the key member 46 moves toward the blade 38, the key member 46 is caused to rotatively move. This rotative movement of the key member 46 is caused by the cam action of the cam slots 57 and the pins 58. Such ro-tative movement of the key member 46 causes rotative movement of the blade 38. This rotative movement of the blade 38 is in a direction to reduce the pitch angle of the blade 38. Each blade 38 may thus appear as shown in broken lines in FIGURE 7 and as shown in FIGURE 8. Therefore, the volume of the air moved by each of the blades 38 is reduced. Thus, the noise caused by the air moved by the blades 38 is reduced.

As the speed of rotation of the hub structure 18 increases, the pitch angle of the blades 38 is further decreased. Such reduction in the pitch angle of the blades 38 occurs as each key member 46 moves farther toward its respective blade 38, as the respective spring 60 is further compressed. On the other hand, if the speed of rotation of the hub structure decreases, there is less centrifugal force urging the key member 46 toward the blade 38. Thus, the key member 46 is moved in a direction from the blade 38. Thus, there is an increase in the pitch angle of the blades 38.

The rotational speed of the hub structure 10 at which the key members 46 overcome the forces of the springs 68 may be predetermined by the preset compression of the springs 60. As stated above, the preset compression of the springs 60 is determined by the nuts 56 which are adjusted upon the respective rods 44 as desired.

Thus, it is to be understood that regardless of the pitch angle of the blades 38, as determined by the thermally responsive material 40, the pitch angle is automatically The amount of reduction of the pitch angle of the blades 38 is dependent upon the rate of rotation of the fan structure. This is due to the fact that as the rate of rotation of the fan structure increases the centrifugal forces acting As centrifugal forces upon the key member 46 increase, the key members 46 tend to move toward the respective blade members 38. As the key members 46 move toward the blade members 38, the pitch angle of the blades is reduced. Thus, the level of noise caused by air moved by the blades 38 never exceeds a given value. However, the angle of pitch of the blades 38 becomes a maximum at temperatures above a given value if the speed of rotation of the hub structure 1-0 is below a given value.

Although the preferred embodiment of the device has been described, it will be understood that within the purview of this invention various changes may be made in the form, details, proportion and arrangement of parts, the combination thereof and mode of operation, which generally stated consist in a device capable of carrying out the objects set forth, as disclosed and defined in the appended claims.

Having thus described my invention, I claim:

1. Fluid control apparatus comprising rotary support structure, a plurality of blade structures pivotally carried by the support structure, cam means joining the support structure to each of the blade structures, thermally responsive force transmission means carried by each of the blade structures and operably connected to the cam means so that there is pivotal movement of the blade structures with operation of the thermally responsive force transmission means, the cam means including resilient means permitting adjustment of the pivotal position of the blade structure with respect to the support structure in response to changes in centrifugal forces acting upon the cam means.

2. Fan mechanism comprising a hub, a plurality of stems rotatably carried by the hub, each of the stems having an extension portion spaced from the hub, a plurality of fan blades, there being a fan blade rigidly attached to each extension portion, each stem having a cavity, there being a quantity of thermally responsive pressure material within the cavity of each stem, a plurality of axially movable piston members, there being a piston member for each of the stems, each piston member having a portion within the cavity of its respective stem, the cavity of each stem having a key portion, a key member axially movable within the key portion of each stem, resilient means disposed between each key member and its respective piston member, each key member having a cam portion exterior of the stem, a plurality of engagement members carried by the hub, there being one engagement member adjacent each of the stems and engageable by the cam portion of its respective key member, pressure of the pressure material within each stem causing movement of the respective piston member thus causing rotative movement of the key member as the cam portion of the key member engages the engagement member, thus causing rotative movement of the stem so that there is rotative movement of the fan blade, sufficient centrifugal force upon each key member causing changes in the resilient means of the respective stem so that the stem and the blade are rotatively moved by the change in relative positions of the key member and the engagement member.

3. Fan apparatus comprising rotary support structure, a plurality of blade members, rotative means attaching the blade members to the support structure, thermally responsive work producing means operably connected to the rotative means for rotation of the blade members upon subjection of the thermally responsive work producing means to a temperature above a given value, and resilient means intermediate the thermally responsive work producing means and the rotative means permitting adjustment of the rotative position of the blade members in accordance with centrifugal forces applied to the rotative means.

4. Fan apparatus comprising rotary support structure, a plurality of stem members rotatably supported by the support structure, a plurality of blade members, there being one blade member carried by each of the stem members, each stem member being provided with a cavity therein, a plurality of plunger members, there being one plunger member at least partially disposed within each of the stem members, each plunger member being axially movable with respect to its respective stem member, thermally responsive work producing means within the cavity of each stem member and operable to axially move the plunger member thereof, a plurality of key members, each key member having an engagement portion within one of the stem members for rotation of the stem member with rotation of the key member, each key member being axially movable with respect to its respective stem member, each key member having an extension portion provided with a cam surface, a plurality of cam engagement members carried by the support structure, there being a cam engagement member engageable with the cam surface of each extension portion so that axial movement of the key member results in rotative movement thereof, a plurality of resilient members, there being one resilient member disposed intermediate each plunger and its respective key member for transmission of forces between the key member and the plunger member.

5. Apparatus of the type described comprising rotary support structure, a plurality of blade assemblies rotatively carried by the support structure, a plurality of thermally responsive actuator assemblies, there being one thermally responsive actuator assembly for each of the blade assemblies, each actuator assembly including key means engageable with its respective blade assembly for rotation of the blade assembly with rotation of the key means, the key means being axially movable, each actuator assembly also including thermally responsive actuator means, and resilient means, the resilient means being intermediate the key means and the thermally responsive actuator means, and cam means joining the key means of each of the thermally responsive actuator assemblies to the support structure so that the key means is rotated with axial movement thereof, the resilient means permitting relative movement between the key means and the thermally responsive actuator means.

6. Adjustable pitch fan mechanism comprising rotary support structure, a plurality of blade assemblies rotatably carried by the support structure, thermally responsive actuator means carried by each of the blade assemblies, the thermally responsive actuator means including a thermally responsive power unit, each actuator means also including cam means for rotation thereof, each actuator means also including key means for rotation of its respective blade assembly with rotation of the actuator means, each actuator means also including resilient means disposed intermediate the power unit and the cam means, the resilient means permitting relative movement between the power unit and the cam means.

7. Fan apparatus comprising rotary support structure, a plurality of blade members rotatably carried by the support structure, thermally operable means carried by each of the blade members, a plurality of rotatable and axially movable key members, each key member having an engagement portion engageable with one of the blade members for rotation thereof with rotation of the key member, and a plurality of resilient members, there being one resilient member intermediate the thermally operable means of each blade member and its respective key member permitting relative movement between the key member and the thermally operable means.

8. Fan apparatus comprising rotary support structure, a stem rotatively attached to the support structure and extending therefrom, the stem being provided with a cavity therein, a quantity of thermally expansive material within the cavity, a plunger within the cavity and movable by the thermally expansive material, a key member axially movable within the stem, a rod attached to the plunger and extending through the stem, a stop member adjustably attached to the rod adjacent the end thereof opposite the plunger, the stop member being in engagement with the key member, a coil spring encompassing the rod and disposed intermediate the plunger and the key member, the coil spring being retained in compression, the compression of the coil spring being determined by the adjustment of the stop member with respect to the rod and with respect to the plunger, the key member having an engagement portion, the stern having a portion complementary to the engagement portion and engageable thereby for rotation of the stem with rotation of the key member, the key member having a cam portion, cam engagement means carried by the rotary support structure and engageable by the cam portion of the key member so that there is rotative movement of the key member with axial movement thereof, forces between the plunger and the key member thus being transmitted through the coil spring.

9. Adjustable pitch fan apparatus comprising rotary support structure, a'plurality of blade members rotatively carried by the support structure, each :blade member having a cavity therein, thermally responsive material within the cavity of each blade member, a plurality of pistons, there being a piston Within the cavity of each blade member and movable by the thermally responsive material, each blade member having a key engagement portion, a plurality of key members, there being a key member engageable with the key engagement portion of each blade member, each member being rotatively and axially movable, rotation of each key member causing rotation of its respective blade member, each key member having a cam portion, a plurality of cam engagement members carried by the support structure, there being a cam engagement member engageable by the cam portion of each one of the key members for rotation of the key member with axial movement thereof, a plurality of compression springs, there being a compression spring disposed intermediate each piston and its respective key member so that relative movement between the piston and the key member is permitted.

10. Fan apparatus comprising:

rotary support structure;

a plurality of stem members rotatably carried by the support structure; a plurality of blade members, there being one blade member rigidly secured to each stem member;

a plurality of key members, there being a key member in engagement with each of the stem members, each key member being axially movable with respect to its respective stem member, each key member and its respective stem member being provided with complementary engagement portions so that the stem member and the key member rotate together;

thermally responsive means carried by the blade members;

resilient intermediate means disposed intermediate each key member and the thermally responsive means, the thermally responsive means forcing movement of the resilient intermediate means causing axial movement of the key members;

cam means carried by the support structure and by each key member causing rotation of the key member with axial movement thereof.

References Cited in they file of this patent UNITED STATES PATENTS 1,267,975 Coats May 28, 1918 2,416,541 Olman Feb. 25, 1947 2,547,037 Morelock Apr. 3, 1951 2,949,735 Stefucza Aug. 23, 1960 FOREIGN PATENTS 460,921 Great Britain Feb. 8, 1937 

1. A FLUID CONTROL APPARATUS COMPRISING ROTARY SUPPORT STRUCTURE, A PLURALITY OF BLADE STRUCTURES PIVOTALLY CARRIED BY THE SUPPORT STRUCTURE, CAM MEANS JOINING THE SUPPORT STRUCTURE TO EACH OF THE BLADE STRUCTURES, THERMALLY RESPONSIVE FORCE TRANSMISSION MEANS CARRIED BY EACH OF THE BLADE STRUCTURES AND OPERABLY CONNECTED TO THE CAM MEANS SO THAT THERE IS PIVOTAL MOVEMENT OF THE BLADE STRUCTURES WITH OPERATION OF THE THERMALLY RESPONSIVE FORCE TRANSMISSION MEANS, THE CAM MEANS INCLUDING RESILIENT MEANS PERMITTING ADJUSTMENT OF THE PIVOTAL POSITION OF THE BLADE STRUCTURE WITH RESPECT TO THE SUPPORT STRUCTURE IN RESPONSE TO CHANGES IN CENTRIFUGAL FORCES ACTING UPON THE CAM MEANS. 